The present invention relates to a device for controlling the locking and unlocking operations of a gear wheel-rotary disc assembly, and an apparatus including such a device.
The field of the invention is that of implements provided for driving the locking and unlocking operations of a rotary disc or platform such as the rotary table of a transfer apparatus, a rotary table conveyor and the like in which, after the rotary movement, the locking operation is performed by means of a gear wheel coupling system (for example of the HIRT's type).
In such an application, the rotary disc can perform axial movements, i.e.:
a movement or stroke in which the rotary disc is moved toward the apparatus bed, at the end of which displacement, the teeth of the movable gear wheel, provided on the rotary disc, engage with corresponding teeth of a fixed gear wheel provided on the apparatus bed; this position corresponding to a locking or stop condition of the rotary disc; PA1 and a movement or stroke in which the rotary disc is driven away from the apparatus bed, at the end of which movement, the teeth of the movable gear wheel are fully disengaged from those of the fixed wheel; this position corresponding to an unlocking condition of the rotary disc which, accordingly, can freely rotate.
The above disclosed axial movements of the rotary disc are conventionally performed by using hydraulic or pneumatic cylinder-piston assembly which, however, cannot provide a very accurate driving of the rotary disc, which, in modern digitally controlled apparatus must turn with a very high speed. Thus, prior apparatus including the disclosed rotary disc assembly operate with a comparatively low speed and, moreover, they are noisy and their operating precision is frequently unsatisfactory. Under particular operating conditions, moreover, the mentioned drawbacks could cause failures of the gear wheels, because of an interference meshing of the teeth of the movable gear wheel with those of the fixed gear wheel, with the rotary disc in a rotary condition.